> Thanks for the information that = (self classify) may not be the > most efficient approach for the machine, but pedagogically there > may be conceptual advantages to giving the learner a single step > solution, compared to the i.~ which would require an explanation > of adverbs as well. Once again I am finding the fastest way to > learn is to teach (or attempt to teach ;) )
As far as the beginner is concerned, both = and i.~ are single step. You don't necessarily have to explain the expression; instead, you can explain the result: x=: 'mississippi' = x 1 0 0 0 0 0 0 0 0 0 0 0 1 0 0 1 0 0 1 0 0 1 0 0 1 1 0 1 1 0 0 0 0 0 0 0 0 0 0 0 0 1 1 0 i.~ x 0 1 2 2 1 2 2 1 8 8 1 x i. x 0 1 2 2 1 2 2 1 8 8 1 0 1 2 3 4 5 6 7 8 9 10 m i s s i s s i p p i 0 1 2 2 1 2 2 1 8 8 1 I wasn't not necessarily talking about machine efficiency. =x takes more room on the screen, and in your brain. ----- Original Message ----- From: bob therriault <[email protected]> Date: Tuesday, February 2, 2010 10:50 Subject: Re: [Jprogramming] The Ambiguous Dictionary To: Programming forum <[email protected]> > Thanks Roger, > > I had been thinking about using + (plus) as well because it can > generalize as a template to other arithmetic 0 rank dyadic > verbs. Your examples provide a starting point for the concepts. > I'll see what I can come up with. > > Thanks for the information that = (self classify) may not be the > most efficient approach for the machine, but pedagogically there > may be conceptual advantages to giving the learner a single step > solution, compared to the i.~ which would require an explanation > of adverbs as well. Once again I am finding the fastest way to > learn is to teach (or attempt to teach ;) ) > > cheers, bob > > On -Feb2-2010, at -Feb2-20109:47 AM, Roger Hui wrote: > > >> Take a J primitive which is relatively simple but maybe hard > for a > >> beginner to intuit, like monadic "=" (self-classify). Not something > >> with bells and whistles like ";:". Personally I'd like to see an > >> animation of self-classify, because coming from APL I'm still not > >> altogether comfy with it in my own mind. > > > > Use + (plus). It'd be so "obvious" that the viewer/reader > > would think "How else would you have it?" > > > > 2 + 3 > > 5 > > > > 2 + 3 4 5 > > 5 6 7 > > 20 30 10 + 7 > > 27 37 17 > > > > 20 30 10 + 3 4 5 > > 23 34 15 > > 20 30 + 3 4 5 > > |length error > > | 20 30 +3 4 5 > > > > i. 3 4 > > 0 1 2 3 > > 4 5 6 7 > > 8 9 10 11 > > > > 2 + i.3 4 > > 2 3 4 5 > > 6 7 8 9 > > 10 11 12 13 > > 20 40 60 + i.3 4 > > 20 21 22 23 > > 44 45 46 47 > > 68 69 70 71 > > (i.3 4) + 100 200 19 > > 100 101 102 103 > > 204 205 206 207 > > 27 28 29 30 > > 20 40 60 80 + i.3 4 > > |length error > > | 20 40 60 80 +i.3 4 > > > > (i.3 4) + (10 + i.3 4) > > 10 12 14 16 > > 18 20 22 24 > > 26 28 30 32 > > > > p.s. I believe that the current monadic = is not one of > > the better verbs in J. The representation is wasteful, > being > > approximately O(n^2), and if the representation is wasteful > > then the implementation is necessarily wasteful. > > For self-classification i.~ is much better. Moreover, > the "key" adverb > > (not available at the time the monad = was first defined) > > has made a self-classification verb much less needed. > > > > > > > > ----- Original Message ----- > > From: Ian Clark <[email protected]> > > Date: Tuesday, February 2, 2010 8:59 > > Subject: Re: [Jprogramming] The Ambiguous Dictionary > > To: Programming forum <[email protected]> > > > >> URL embedding is something I must leave to others. I'd be starting > >> from cold as regards Moinmoin. Maybe we should simply fall > back on > >> html? Remind me why we need anything fancier. > >> > >> Voice-over I have strong feelings against. Distracting, ineffective > >> and culturally dependent. Traditional and reassuring maybe, > but only > >> in your own mother tongue, accent and mannerisms. Nothing > going for > >> it. > >> > >> And I say that as an ex-lecturer (and courseware developer). > >> > >> Use soothing music. It's only wallpaper. And then only in a YouTube > >> showcase, not in a serious expository text. > >> > >> The same goes for moving text, or "titles" as I think movie makers > >> call them. Only good for identifying the footage, like a > >> clapper-board. The effort to read it can distract the viewer > >> from the > >> object you want him/her to attend to. There will always be > >> accompanying text. I think the purpose of animation in technical > >> exposition is to convey spatial concepts non-verbally. Therefore > >> verbiage is nothing but a distraction. > >> > >> I like your use of coloured dots. It conveys succintly that the > >> content of a given cell doesn't matter: just the interplay between > >> cells. If you use numbers, or even letters, the viewer wastes > >> brain-cycles processing these before grasping they are of no > >> importance. If you need more modal dimensions: shape and > size. As > >> regards shape, chicks and tadpoles may be slightly better > than squares > >> and circles, but one must balance being boring against being > >> distracting. I'd err on the "boring" side to start with, and > >> spice-up > >> judiciously. People assume animations have got to be Loony > >> Toons. But > >> someone prepared to consider programming in any language, let > >> alone J, > >> needs an attention-span longer than a 5 year old TV watcher. > >> > >> The viewer may have to study the animation for quite some > time to > >> absorb its principle. Eye candy soon gets irritating. See the > >> "grasshopper escapement" animation, halfway down in > >> http://en.wikipedia.org/wiki/John_Harrison -and work out how it > >> manages to be friction-free. Jiminy Cricket would soon begin > to grate. > >> > >> Further to that example, I think continuous animation loops > are good. > >> (Though it's nice to be able to stop 'em!) > >> > >> Take a J primitive which is relatively simple but maybe hard > for a > >> beginner to intuit, like monadic "=" (self-classify). Not something > >> with bells and whistles like ";:". Personally I'd like to see an > >> animation of self-classify, because coming from APL I'm still not > >> altogether comfy with it in my own mind. > >> > >> And remember the better it conveys its message, the more > trivial and > >> "obvious" it looks and the less time the viewer spends > looking > >> at it. > >> It's why writers of public notices are always too pompous and > prolix:>> they don't want to appear dumb. It's really quite > unrewarding > >> work, in > >> a way. > >> > >> Ian > >> > >> > >> On Tue, Feb 2, 2010 at 5:56 AM, bob therriault > >> <[email protected]> wrote: > >>> Thanks for the review, Ian > >>> > >>> It definitely needs to be sped up and, although music could > be > >> added, it was going to be finished with a voice over and > sound > >> effects. I hadn't got around to final version, but when I > read > >> Oleg's comment about animation, I exported the 'work in > >> progress' to YouTube. YouTube does provide a string for > >> embedding, but I didn't think it would work within an email. > >>> > >>> I would be happy to work on animations as they were needed > for > >> specific primitives. My experience says that there is a > certain > >> level of fundamental understanding that is required before > >> animations are really effective, before that they tend > towards > >> eye-candy (or worse misleading). If you have a primitive in > mind > >> let me know and we can go through some iterations to see how > >> productive we are. > >>> > >>> Cheers, bob > >>> > >>> ps. you can put videos into J labs as well, by using the > >> jbrowser file and calling specific URL's hiding it within the > >> PREPARE section. > >>> eg. > >>> PREPARE > >>> launch_jbrowser_ 'http://www.apple.com/ca/ipodtouch/what- > >> is/pocket-computer.html' > >>> PREPARE > >>> It has been a while since I have done this and the result is > >> that a whole browser window will open, but when refined this > may > >> have some possibilities. I'm not as sure how this will work > with > >> the new browser interface. bt > >>> > >>> On -Feb1-2010, at -Feb1-20106:43 PM, Ian Clark wrote: > >>> > >>>> I like it, Bob. > >>>> > >>>> The minimalism may arise from it being a first effort, but > it shows > >>>> it's neither necessary nor wise to over-egg the pudding. > >>>> > >>>> Minor crits: could do with being sped up. Needs music. > >> YouTube has a > >>>> library of free soundtracks: you can just attach one for now. > >>>> > >>>> YouTube movies can be easily embedded in your own html > file. > >> Stefano & > >>>> I have done it. They generate you an <object> to > >> copy/paste. See > >>>> source of > http://www.maxclark.me.uk/undeadtree/interspex.htm > >> for an > >>>> example. > >>>> > >>>> But how to do it with MoinMoin? > >>>> > >>>> So... are you offering to do a 15 second movie for each J > >> primitive?>> > >>>> Ian > >>>> > >>>> > >>>> On Mon, Feb 1, 2010 at 10:08 PM, bob therriault > >> <[email protected]> wrote: > >>>>> Hi Oleg and Ian, > >>>>> > >>>>> http://www.youtube.com/watch?v=ODxv498p4ME > >>>>> > >>>>> This isn't about a specific function, but is an animation > i > >> put together to explain why it is useful to organize > information > >> into arrays. I developed it on keynote, but haven't yet put a > >> soundtrack to it. It's not really high end, but it wasn't too > >> hard to put together either. Let me know if you have more > >> specific ideas for animations. > >>>>> > >>>>> Cheers, bob > >>>>> > >>>>> On -Feb1-2010, at -Feb1-201012:50 PM, Oleg Kobchenko wrote: > >>>>> > >>>>>>> From: Ian Clark <[email protected]> > >>>>>> > >>>>>>> > >>>>>>>> One winning instructional strategy, including Gilman > and Rose, > >>>>>>>> is telling a story for each piece of material. Such stories, > >>>>>>>> among other things, may revolve around exo-paradigms. > >>>>>>> > >>>>>>> When I used to program in FORTH (sign of a mis-spent > >> youth) one > >>>>>>> well-beloved primer in the FORTH community was > illustrated with > >>>>>>> engaging but instructive cartoons. Thus the standard > word > >> SWOP was a > >>>>>>> little two-headed dragon that did what you'd guess with > >> objects on the > >>>>>>> stack. Can anyone remember the book and remind me of its > title?>>>>>> > >>>>>> Starting FORTH, by Leo Brodie > >>>>>> > >>>>>> http://www.forth.com/starting-forth/sf2/sf2.html > >>>>>> > >>>>>> > >>>>>> This is fun stuff all right. And a good read for a vacation. > >>>>>> > >>>>>> > >>>>>> What I was thinking for APL/J for a long time was > >>>>>> an interactive or animated illustrator of the operations, > >>>>>> especially those that manipulate multidimensional and > >>>>>> nested structures. > >>>>>> > >>>>>> > >>>>>>> I know someone (http://www.leelamaria.com/) who could do > >> us a wodge of > >>>>>>> cartoons like that. Shall I try to get them interested? ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
